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Item Open Access Depth of influence of rolling dynamic compaction(ICE Publishing, 2021) Scott, B.T.; Jaksa, M.; Mitchell, P.W.The depth of influence of rolling dynamic compaction (RDC) was investigated in a field trial using a four-sided impact roller. Earth pressure cells (EPCs) were placed at varying depths at a site consisting of homogeneous soil conditions. EPCs measured pressures imparted by RDC at 3·85 m depth; however, the largest magnitudes of pressure were confined to the top 2 m beneath the ground surface. These results were complemented by field density data, penetrometer and geophysical testing. A number of published case studies using the 8 t four-sided impact roller, for either improving ground in situ or compacting soil in thick layers, are summarised in this paper. Finally, equations are presented that predict first, the effective depth of improvement, appropriate for determining the depth to which the ground can be significantly improved in situ, and, second, the depth of major improvement for RDC, appropriate for thick-layer compaction.Item Restricted History on the rocks(UNSW Press, 2025) Rademaker, L.; May, S.; Goldhahn, J.; Maralngurra, G.; McGrath, A.; Huggins, J.Item Open Access Prelithiation strategies for silicon-based anode in high energy density lithium-ion battery(Elsevier BV, 2022) Jia, T.; Zhong, G.; Lv, Y.; Li, N.; Liu, Y.; Yu, X.; Zou, J.; Chen, Z.; Peng, L.; Kang, F.; Cao, Y.Green energy storage devices play vital roles in reducing fossil fuel emissions and achieving carbon neutrality by 2050. Growing markets for portable electronics and electric vehicles create tremendous demand for advanced lithium-ion batteries (LIBs) with high power and energy density, and novel electrode material with high capacity and energy density is one of the keys to next-generation LIBs. Silicon-based materials, with high specific capacity, abundant natural resources, high-level safety and environmental friendliness, are quite promising alternative anode materials. However, significant volume expansion and redundant side reactions with electrolytes lead to active lithium loss and decreased coulombic efficiency (CE) of silicon-based material, which hinders the commercial application of silicon-based anode. Prelithiation, preembedding extra lithium ions in the electrodes, is a promising approach to replenish the lithium loss during cycling. Recent progress on prelithiation strategies for silicon-based anode, including electrochemical method, chemical method, direct contact method, and active material method, and their practical potentials are reviewed and prospected here. The development of advanced Si-based material and prelithiation technologies is expected to provide promising approaches for the large-scale application of silicon-based materials.Item Metadata only Digesting the pathogenesis of diabetic gastroparesis(Elsevier, 2021) Jalleh, R.J.; Marathe, C.S.; Jones, K.L.; Horowitz, M.; Rayner, C.K.Abstract unavailableItem Metadata only SARS-CoV-2 Infection and Childhood Islet Autoimmunity(American Medical Association, 2025) Walker, G.J.; Mallitt, K.-A.; Craig, M.E.; Ashwood, P.; Barry, S.C.; Brown, J.D.; Caguicla, J.; Davis, E.A.; Hamilton-Williams, E.E.; Harrison, L.C.; Haynes, A.; Huynh, T.; Martin, G.; McGorm, K.J.; Morahan, G.; Naing, Z.; Oakey, H.; Penno, M.A.S.; Sevendal, A.; Sinnott, R.O.; et al.This cohort study examines whether there is a temporal association between SARS-CoV-2 infection and the development of islet autoimmunity among Australian children with a first-degree relative with type 1 diabetes.Item Metadata only Seeing a lot of mobile speed cameras on your summer road trips? Here's how they work(The Conversation, 2023) Raftery, S.Item Restricted Net Zero Carbon Policies in the Construction Industry(Springer Nature, 2025) Rodrigo, N.; Jayathilaka, W.W.; Domingo, N.; Senaratne, S.; Wilkinson, S.; Perera, S.The buildings and construction industry was responsible for 30% of the total energy consumption and 26% of the global energy-related emissions that were related to energy and processes in 2022. Concerns about climate change are growing, and as a result, there is an increasing need to implement net zero carbon (NZC) regulations and policies in order to reduce the negative impact that construction activities have on the environment. To achieve a net zero impact on the environment, the policies of the NZC strive to achieve a balance between the amount of carbon dioxide (CO2) that is released into the atmosphere and the amount that is removed or offset. Within the context of the construction industry, this chapter investigates the prospective outcomes, obstacles, and execution of NZC regulations and policies. The regulations and policies related to NZC in the construction industry of nine (9) countries named United States (US), Japan, Germany, South Korea, Canada, China, India, Indonesia, and Saudi Arabia were identified in this chapter. As well as challenges and opportunities related to regulatory compliance were identified by reviewing the current NZC regulations and policies, reports, previous research, and other related documents. Challenges in NZC policies are highlighted along with the opportunities. Action plan for carbon neutrality of the selected countries has been mapped within this chapter. The findings underline that how the developed and developing countries are reflected in their actions in the carbon neutrality path. This study provides a foundation for achieving carbon neutrality of the top carbon-emitting countries through NZC regulations and policies compliance and development. Further, the discussion extends to the need for collaboration between the government, policymakers, construction industry practitioners, and researchers to overcome challenges when stepping forward in the carbon neutralisation path.Item Open Access Pregnancy scanning of sheep in southern Australia. 1. Scanning for litter size was profitable across all modelled regions, times of lambing and genotypes(CSIRO Publishing, 2025) Young, J.M.; Brown, D.J.; Brien, F.D.; Greer, A.Context. Pregnancy scanning allows ewes to be separately managed by litter size class to: (1) meet recommended condition score targets to enhance survival and progeny productivity, (2) prioritise allocation of multiple-bearing ewes to smaller mobs or more sheltered lambing paddocks, and (3) select replacement ewes based on birth type. However, 70% of Australian sheep producers are not scanning for litter size. Aims. To establish the profitability of pregnancy scanning in southern Australia, to build a stronger business case to address the key perception by non-adopters that the case is weak. Methods. The profitability of pregnancy scanning was modelled, across three regions (long, medium and short growing seasons in southern Australia), three different genotypes (Merino, Merino × terminal and a maternal flock) and three lambing times (autumn, winter and spring) using the Australian Farm Optimisation Model. A simpler gross margin analysis was used to include the summer rainfall regions. Key results. Implementing optimal ewe nutritional management, paddock allocation and replacement strategies based on litter size was profitable in all the scenarios of region, genotype, time of lambing and price tested. The increase in profitability in the winter rainfall zone averaged across the scenarios tested was A$5.75/ewe scanned. In the summer rainfall zone, the average increase in profit was A$4.44/ewe scanned. Profitability was sensitive to sheep meat prices, but not sensitive to wool and supplement prices, nor overall reproductive rate. Conclusions. There is a strong business case for pregnancy scanning ewesfor littersize via: (1)selling of non-pregnant ewes(A$1.75/ewe), (2) better allocation of feed based on litter size (A$2.00/ewe), (3) allocating multiple-bearing ewes to the best lambing paddocks and/or reducing mob size to enhance lamb survival (A$1.00/ewe), and (4) accounting for birth type when selecting breeding replacements (A$1.00/ewe). Implications. Pregnancy scanning for litter size is a relatively low-cost, high-profit and vital tool for improving reproductive rate, lamb and ewe survival rates, and lamb growth rates. Our findings extend previous, more limited studies, in terms of their reach across different regions, genotypes and production systems.Item Metadata only Exploring the impact of geometric variation on electromagnetic performance in a coaxial coil system(Current Science Association in collaboration with the Indian Academy of Sciences, 2025) Yang, Y.; Jafari, A.; Robertson, W.; Arjomandi, M.To optimise coil design for creating an efficient electro-magnetic system characterised by high precision, the present study investigates the impact of varying coil geometry on the electromagnetic force generated bet-ween a pair of coaxial cylindrical coils. The study utilises a multifaceted approach to identify the rela-tionships between axial magnetic force, air-gap dis-tance and coil radial thicknesses. Systematic changes in coil geometry are made to understand the sensitivity of electrical power consumption to the generation of magnetic force, and an analytical model is used to un-derstand the relationships. In this article, limitations on the conventional magnetic force computation meth-od established by previous researchers are identified. Additionally, the results indicate that using thicker coils significantly increases magnetic force production. This advantageous amplification is counterbalanced by increased coil resistance, inevitably leading to reduced efficiency of electromagnetic force production. A mathematical model is developed here for computing the coil efficiency, and methods are proposed to simul-taneously optimise the generation of magnetic force by coils while ensuring.Item Metadata only Cyclic alternating pattern (CAP) in children with obstructive sleep apnea and its relationship with adenotonsillectomy, behavior, cognition, and quality-of-life(Oxford University Press, 2021) Hartmann, S.; Bruni, O.; Ferri, R.; Redline, S.; Baumert, M.Study Objectives: To determine in children with obstructive sleep apnea (OSA) the effect of adenotonsillectomy (AT) on the cyclic alternating pattern (CAP) and the relationship between CAP and behavioral, cognitive, and quality-of-life measures. Methods: CAP parameters were analyzed in 365 overnight polysomnographic recordings of children with mild-to-moderate OSA enrolled in the Childhood Adenotonsillectomy Trial (CHAT), randomized to either early AT (eAT) or watchful waiting with supportive care (WWSC). We also analyzed CAP in a subgroup of 72 children with moderate OSA (apnea–hypopnea index > 10) that were part of the CHAT sample. Causal mediation analysis was performed to determine the independent effect of changes in CAP on selected outcome measures. Results: At baseline, a higher number of A1 phases per hour of sleep was significantly associated with worse behavioral functioning (caregiver Behavior Rating Inventory of Executive Function (BRIEF) Global Executive Composite (GEC): ρ = 0.24, p = 0.042; caregiver Conners’ Rating Scale Global Index: ρ = 0.25, p = 0.036) and lower quality of life (OSA-18: ρ = 0.27, p = 0.022; PedsQL: ρ = −0.29, p = 0.015) in the subgroup of children with moderate OSA, but not across the entire sample. At 7-months follow-up, changes in CAP parameters were comparable between the eAT and WWSC arms. CAP changes did not account for significant proportions of variations in behavioral, cognitive, and qualityof- life performance measures at follow-up. Conclusions: We show a significant association between the frequency of slow, high-amplitude waves with behavioral functioning, as well as the quality of life in children with moderate OSA. Early AT in children with mild-to-moderate OSA does not alter the microstructure of nonrapid eye movement sleep compared with watchful waiting after an approximately 7-month period of follow-up. Clinical Trial: The study “A Randomized Controlled Study of Adenotonsillectomy for Children With Obstructive Sleep Apnea Syndrome” was registered at Clinicaltrials.gov (#NCT00560859).Item Open Access Search for triple Higgs boson production in the 6b final state using pp collisions at √s p = 13 TeV with the ATLAS detector(American Physical Society (APS), 2025) Aad, G.; Aakvaag, E.; Abbott, B.; Abdelhameed, S.; Abeling, K.; Abicht, N.J.; Abidi, S.H.; Aboelela, M.; Aboulhorma, A.; Abramowicz, H.; Abulaiti, Y.; Acharya, B.S.; Ackermann, A.; Adam Bourdarios, C.; Adamczyk, L.; Addepalli, S.V.; Addison, M.J.; Adelman, J.; Adiguzel, A.; Adye, T.; et al.A search for the production of three Higgs bosons (𝐻𝐻𝐻) in the 𝑏 ¯ 𝑏 𝑏 ¯ 𝑏 𝑏 ¯ 𝑏 final state is presented. The search uses 126 fb−1 of proton-proton collision data at √𝑠 =13 TeV collected with the ATLAS detector at the Large Hadron Collider. The analysis targets both nonresonant and resonant production of 𝐻𝐻𝐻. The resonant interpretations primarily consider a cascade decay topology of 𝑋 →𝑆𝐻 →𝐻𝐻𝐻 with masses of the new scalars 𝑋 and 𝑆 up to 1.5 and 1 TeV, respectively. In addition to scenarios where 𝑆 is off-shell, the nonresonant interpretation includes a search for Standard Model 𝐻𝐻𝐻 production, with limits on the trilinear and quartic Higgs self-coupling set. No evidence for 𝐻𝐻𝐻 production is observed. An upper limit of 59 fb is set, at the 95% confidence level, on the cross section for Standard Model 𝐻𝐻𝐻 production.Item Metadata only Amorphous self-healed, chopped basalt fiber-reinforced, geopolymer composites(Wiley, 2021) Keane, P.F.; Foltz, J.S.; Chadha, V.; Marsh, C.P.; Kriven, W.M.Geopolymer composites containing refractory, chopped basalt fibers and low-melting glass were made and systematically heat-treated at higher temperatures. Potassiumbased geopolymer of stoichiometric composition K2O·Al2O3·4SiO2·11H2O was produced by high shear mixing from fumed silica, deionized water, potassium hydroxide, (i.e., water glass) and metakaolin. With the addition of low-melting glass (Tm ~815°C) the flexure strengths of the composites increased to ~6 MPa after heat treatment above 900°C to 1100°C. A Weibull statistical analysis was performed showing how the amorphous self-healing effect of the glass frit significantly improved the flexure strength of the geopolymer and ceramic composites after high-temperature exposure. At temperatures up to 900°C, the geopolymer-basalt composite remained amorphous and the low-melting glass frit flowed into the dehydration cracks in the geopolymer matrix. This type of composite could be described as amorphous self-healed geopolymer (ASH-G). At ~1000°C, the geopolymer converted to primarily a crystalline leucite ceramic, but the basalt fiber remained intact, and the melted glass frit flowed and sealed the cracks developed at that temperature. This type of composite could then be described as amorphous self-healed ceramic (ASH-C). A temperature of 1150°C was determined to be optimum as at 1200°C the basalt fibers melted and the strength of the reinforcement was lost in the composites. The amorphous self-healing effect of the glass frit significantly improved the room temperature flexure strength of the heat-treated geopolymer-based composites.Item Restricted Economic evaluation of subcutaneous ketamine injections for treatment resistant depression: A randomised, double-blind, active-controlled trial - The KADS study(Elsevier BV, 2025) Chatterton, M.L.; Perez, J.K.; Thai, T.; Faller, J.; Loo, C.K.; Glozier, N.; Barton, D.; Baune, B.T.; Mills, N.T.; Fitzgerald, P.B.; Glue, P.; Sarma, S.; Hadzi-Pavlovic, D.; Dong, V.; Martin, D.; Mitchell, P.B.; Berk, M.; Carter, G.; Hackett, M.; Hood, S.; et al.BACKGROUND: Ketamine is effective for treatment resistant depression (TRD); but cost-effectiveness evidence remains limited. AIMS: To evaluate the cost-effectiveness of subcutaneous ketamine for TRD from health sector and societal perspectives. METHODS: A cost-utility analysis alongside the KADS randomised controlled trial (RCT) involved 174 participants receiving ketamine or midazolam (active control) twice weekly for 4 weeks. Healthcare resource use, transportation, carer time and lost productivity data were collected via self-reported questionnaire at baseline, end of RCT (week 4) and RCT 4-week follow-up (week 8). Quality-adjusted life years (QALYs) were calculated using AQoL-8D utility values. Initial dosing was fixed (cohort 1) and changed to response-guided dosing (cohort 2). Base-case 1 included control arm treatment costs; base-case 2 excluded these costs. RESULTS: At end of RCT, cohort 2 utility values were significantly higher for ketamine than the control treatment (0.435 vs. 0.352; p < 0.05). Health sector incremental cost-effectiveness ratios (ICERs) in base-case 1 indicated ketamine was dominant (less costly, more effective) with probabilities of falling below $50,000/QALY of 89 % (end of RCT) and 91 % (total across 8-weeks). Societal perspective probabilities were lower (30-32 %). In base-case 2, ketamine was not cost-effective (ICERs: $251,250/QALY at end of RCT; $108,500/QALY across 8-weeks), with minimal probabilities (0-5 %) of falling below $50,000/QALY. CONCLUSIONS: The initial four-week ketamine treatment phase appeared cost-effective from a health sector perspective when including control arm costs, although societal perspective results were less favourable. Excluding control treatment costs highlighted substantial uncertainty, emphasising the importance of selecting an appropriate comparator for an economic evaluation.Item Open Access The Protective Role of Ambient Ultraviolet Radiation Against Dementia: An Ecological Analysis of Global Data.(WILEY, 2025) You, W.Background and Aims: This study investigates the global impact of ambient ultraviolet radiation (UVR) on dementia incidence, addressing its controversial association with dementia risk. UVR, through both vitamin D‐dependent and independent mechanisms, influences physiological processes essential for brain health, such as reducing neuroinflammation, improving sleep regulation, and enhancing neuroplasticity. This study aims to clarify the relationship between UVR and dementia incidence and evaluate its role in public health strategies for dementia prevention. Methods: An ecological analysis across 204 countries was conducted using country‐specific data on UVR levels and dementia incidence rates. Bivariate analysis, partial correlation, and multiple linear regression models were employed to assess the relationship between UVR and dementia incidence. Confounding factors, including aging, economic affluence, genetic predisposition, and urbanization, were controlled to ensure robust results. Subgroup analyses were performed to explore differences across income classifications, regional groupings, and developmental statuses, based on World Bank and United Nations criteria. Results: A significant inverse correlation between UVR and dementia incidence was identified (r = −0.764, p < 0.001), which persisted after adjusting for confounding factors. UVR emerged as the strongest predictor of dementia incidence, explaining a substantial portion of the variance, followed by aging as the second strongest predictor. Subgroup analyses revealed that the protective effects of UVR were particularly pronounced in developing countries, where limited access to vitamin D supplementation, combined with greater exposure to natural sunlight may enhance its influence. Conclusion: Lower ambient UVR levels are associated with higher dementia incidence rates worldwide, suggesting a critical role for UVR in mitigating dementia risk. Public health strategies should consider environmental factors like UVR, particularly in regions with limited sunlight. Incorporating interventions to optimize UVR exposure could offer a cost‐effective approach to reducing the global dementia burden and improving brain health outcomes.Item Metadata only Eco-economic comparison of batteries and pumped-hydro systems at the micro scale in buildings(Elsevier BV, 2024) Boroomandnia, A.; Rismanchi, B.; Wu, W.; Anderson, R.Expanding the sustainable energy storage capacity is important due to the growth of renewable energy supplies. As pumped storage and utility-scale batteries are two important methods of energy storage, this study investigates the sustainability of micro pumped storage (MPS) units compared to lithium-ion (Li-ion) batteries for electricity storage. The analysis focuses on the levelised cost of storage (LCOS) and levelised embodied emissions (LEE) for small-scale energy storage solutions within the Australian context. This research aims to identify MPS configurations that are economically and environmentally competitive with Li-ion batteries, determine the minimum rooftop area for MPS efficiency, and assess MPS energy storage capacity at an urban scale. The analysis includes three upper water storage options: Modular Tank (T), Green Roof (GR), and Blue Roof (BR); and two lower storage configurations: Modular Tank and Nearby Stream (S). These configurations are coded by the notation: upper storage type/lower storage type, and are evaluated across buildings of varying heights. The results show that MPS has a significant economic advantage over Li-ion batteries as storage capacity increases, particularly in configurations applied T for upper water storage. MPS outperforms Li-ion in buildings over 150, 50, 100, and 50 m height for T/T, T/S, GR/T, and GR/S configurations respectively. Environmentally, MPS configurations generally have lower LEE than Li-ion batteries, with GR setups demonstrating the most significant benefits, while BR configurations have higher emissions. The study also identifies the minimum rooftop area required for MPS installations to be viable, showing that incorporating nearby streams can enhance the feasibility of MPS in buildings with smaller rooftops. However, the findings reveal that MPS systems are generally less advantageous than battery systems for buildings with rooftop areas smaller than 1,175 m2. Finally, despite only up to 28 buildings in Melbourne meeting the optimal MPS criteria, the ability to store up to 14 MWh/day confirms MPS as a viable, sustainable alternative to Li-ion batteries under specific conditions, contributing to global sustainable energy efforts.Item Metadata only Transnational recycling of Australian export waste: An exploratory study(Elsevier BV, 2023) Du, L.; Zuo, J.; O'Farrell, K.; Chang, R.; Zillante, G.; Li, L.Transnational recycling of waste is a common phenomenon and can have significant environmental and economic impacts on both exporting and importing countries. However, current studies mainly focused on the management of transnational waste recycling in waste-importing countries, and less attention has been paid to issues related to waste-exporting countries. Using Australian export waste data as an example, combining geospatial analysis methods, this study innovatively analyzes the transnational recycling of waste from the perspective of waste exporting countries. The results show that exported waste, assumed to be recycled in the Australian waste statistics, is not fully recycled by waste-importing countries. This study also combines regression analysis to identify factors associated with the destination of waste exports. The results indicate that there is no statistically significant relationship between environmental factors and the location of the destination when exporting waste. Besides, due to the lack of data, waste-exporting countries do not understand the fate of their exported waste and therefore cannot make choices based on the associated environmental impacts. It is recommended that waste-exporting and -importing countries work together to track data so that environmental impacts of exported waste can be better understood.Item Metadata only Influence of tumour grade on disease survival in male breast cancer patients: a systematic review.(Springer, 2024) Kinsey-Trotman, S.; Nguyen, A.; Edwards, S.; Swalling, A.; Dasari, P.; Walsh, D.; Ingman, W.V.Purpose Histological grading of tumours is a well-established biomarker used to guide treatment in female breast cancer. However, its significance in male breast cancer remains unclear. This systematic review investigates the prognostic significance of tumour grade in relation to breast cancer-specific survival (BCSS) in male breast cancer patients undergoing surgery. Methods MEDLINE, PUBMED Central and EMBASE databases were searched to identify randomised trials and observational studies related to male breast neoplasms, tumour grading, recurrence, and survival. Results A total of fifteen observational type studies were included in the review. A significant association between tumour grade and BCSS was reported in a majority of studies. This association was most evident with regard to high-grade (grade III) compared to low grade (grade I) tumours, with a significant relationship in 4 out of 4 studies. For intermediate-grade II tumours an association was demonstrated in a minority of studies. Conclusions This study confirms an association between high-grade male breast cancers and poorer disease-specific survival, however, the significance of intermediate-grade tumours remains unclear. Further research is required to investigate the biology of male breast cancer in relation to histological grade and optimally define intermediate-grade disease.Item Metadata only Preclinical and clinical evaluation through serial colonoscopic evaluation of neratinib-induced diarrhea in HER2-positive breast cancer-A pilot study.(Wiley, 2024) Bowen, J.; Braga, S.; Zotto, V.D.; Finnie, J.; DiPrimeo, D.; Cooke, B.; Bischof, G.F.; Wong, A.; Di Palma, J.A.The irreversible pan-HER tyrosine kinase inhibitor neratinib is approved for patients with HER2-positive, early-stage and metastatic breast cancer (BC). Neratinib-associated diarrhea is the most common reason for early discontinuation. Preclinical studies identified mechanisms of neratinib-induced diarrhea and rationale for prophylactic and preventive measures. We studied effects of neratinib on rat intestines and conducted a phase 2 study of colon pathogenesis in patients with HER2-positive BC treated with neratinib (NCT04366713). Colon samples from female albino Wistar rats receiving neratinib or vehicle were examined for histopathological changes. Patients with HER2-positive BC received neratinib 240 mg once daily for up to 1 year. Colonoscopy biopsies were collected at baseline and at Day 28 to identify changes consistent with rat pathologies. Rat colons were markedly altered in appearance, with similar short circuit currents (Isc) and responses to carbachol and forskolin. Mucosal barrier loss and/or significant increase in secretory propensity in neratinib-versus control-treated animals were not seen. Two of four endpoint-evaluable patients presented with mild pathological changes, largely comparable with the rat model. Preclinical evidence supports an inflammatory component of neratinib-induced diarrhea without mucosal barrier function loss. Colonoscopy findings in patients with BC indicate mild or no pathological changes in the colon due to neratinib treatment.Item Metadata only Consuming place: Women, wine and imagination(WILEY, 2024) Aujard, J.This paper examines wine drinking among English and Australian women to discover and analyse the connection between their consumption of wine and their experiences, thoughts and imaginings. Comparing the experiences of women from the English town of Halifax with women from the southern suburbs of Adelaide and McLaren Vale (South Australia), I show how imbibing wine enables both groups of women to consume place, space and time, thus extending a liminal experience. Importantly, both groups of women engage with notions of national or regional identity. However, whereas English women typically experience wine drinking as a temporal engagement of social imagination involving a form of armchair alco-tourism, Australian women mostly engage their social memory, and experience wine drinking as embedded within imagined communities of belonging. As such, this study demonstrates that wine drinking is not just gendered, but a complex, culturally situated practice and experience.Item Metadata only CEO-employee pay ratio and labor investment efficiency(Elsevier BV, 2024) Li, Y.; Cheong, C.S.; Canil, J.This paper investigates the impact of CEO-to-median employee pay ratios on labor investment efficiency. Drawing on competing predictions from Talent Assignment Theory and Equity Theory, we examine how pay disparity between CEOs and average workers influences suboptimal investment in labor (labeled inefficient investment in labor). Our analysis finds a significant negative relationship between pay ratios and inefficient investment in labor, suggesting firms with higher CEO compensation exhibit more balanced labor investments. This challenges Equity Theory, which hypothesizes that large intra-firm pay gaps cause perceived unfairness and underinvestment in labor. Overall, the study provides novel evidence on how CEO pay practices shape employee behaviors and factor inputs. The findings contribute to ongoing debates regarding the economic implications of CEO compensation, particularly in optimizing human capital efficiency.